Method of forming sole and sole structure with shoe nail coupled thereto and sole structure with shoe nail

ABSTRACT

A method of forming a sole and a sole structure with shoe nails coupled thereto and the sole structure with the shoe nails are provided. The method includes pre-forming shoe nails, putting the shoe nails in an injection molding mold, injecting a thermally molten sole material into a mold in a manner that the sole material covers inner and outer surfaces of the shoe nails, and performing a cooling process whereby the sole material solidifies and turns into a sole which is then coupled to the shoe nails. The method enables a sole with shoe nails to be quickly manufactured so easily that it increases production efficiency and economic benefits.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to methods of manufacturing parts and components of shoes, and more particularly, to a method of forming a sole and a sole structure with shoe nails coupled thereto and the sole structure with the shoe nails.

2. Description of Related Art

Shoe nails, also known as foot nails, are disposed mostly in a sole of a football shoe or a track and field sports shoe to reduce vibration, increase grip, and enhance control. Referring to FIG. 1, a conventional sole 10 with a plurality of shoe nails 11 coupled thereto. The shoe nails 11 are made of metal. The shoe nails 11 are each fastened to the sole 10 by a bolt 111, and then the sole 10 is coupled to a shoe body. The aforesaid manufacturing process is intricate and thus unfit for mass production.

In view of this, a method of manufacturing a sole with shoe nails was disclosed, which requires performing an instance of injection molding using two types of plastic which are different in material characteristics in order to enhance production efficiency. However, although shoe nails are different from a sole in material characteristics, both the shoe nails and the sole are made of plastic; as a result, the grip of the shoe nails is not up to standard, and thus there is still room for improvement.

The prior art further discloses a sole with shoe nails made of rubber, wherein the sole is made of plastic, and the shoe nails are made of rubber. Since rubber differs from plastic in terms of forming conditions and manufacturing techniques, conventional forming techniques are unfit to form a rubber part and a plastic part simultaneously, and thus it is necessary to pre-form the rubber parts and the plastic part separately before performing a dispensing and adhering procedure or a coupling procedure on the rubber part and the plastic part separately. A failure to control precisely the degree of uniformity in dispensing the plastic during the dispensing step leads to low coupling stability.

SUMMARY OF THE INVENTION

The present invention provides a method of forming a sole and a sole structure with shoe nails coupled thereto and the sole structure with the shoe nails to overcome drawbacks of the prior art, namely intricate manufacturing process, insufficient grip, and low coupling stability.

In order to achieve the above and other objectives, the present invention provides a method of forming a sole and a sole structure with shoe nails coupled thereto. The method comprises the steps as follows:

shoe nail pre-forming step: forming shoe nails each having a head and a coupling segment, with the coupling segment extending in an axial direction, wherein the axial direction is perpendicular to a radial direction, wherein an outer diameter of the coupling segment is less than an outer diameter of the head such that a filling ring portion is formed between the head and the coupling segment, wherein, an end of the coupling segment is connected to the head, wherein a slot is disposed at another end of the coupling segment and has a slot bottom and a slot inner diameter, wherein the slot penetrates the coupling segment in the radial direction;

shoe nail feeding step: putting the pre-formed shoe nails in a first mold, wherein the first mold has a shaping chamber, and the shaping chamber has an opening, wherein, after the shoe nails have been received in the shaping chamber, a shaping space is defined by and between the shoe nails and the opening of the shaping chamber;

die closing step: closing a second mold and the first mold, wherein the second mold has a corresponding forming portion protruding to form a plurality of expanding pins, wherein the expanding pins each have an expanding segment and a guiding segment connected to the expanding segment, wherein the expanding segment has an expanding segment outer diameter, wherein the expanding segment outer diameter is larger than the slot inner diameter, wherein the guiding segment is a conic structure which tapers away from the expanding segment, wherein a guiding end is disposed at an end of the guiding segment and extends away from the expanding segment, wherein the guiding end has a guiding end outer diameter, with the guiding end outer diameter being equal to the slot inner diameter, wherein a feeding passage penetrates the corresponding forming portion of the second mold, wherein the corresponding forming portion of the second mold faces the shaping chamber, so as to close the second mold and the first mold, seal the opening, and enable communication between the feeding passage and the shaping space, wherein, as soon as the corresponding forming portion seals the opening exactly, not only are the guiding ends of the expanding pins inserted into the slots of the shoe nails, respectively, but the guiding ends of the expanding pins also guide the guiding segments into the slots to abut against the slots and thus allow the slots to expand, respectively, wherein a feeding space is defined by and between the guiding end and the slot bottom;

sole material injecting step: heating and melting a sole material to a liquid state, followed by injecting the molten sole material into a space between the first mold and the second mold via the feeding passage;

forming binding step: filling the shaping space, the filling ring portion, and the feeding space with the thermally molten sole material after the sole material has been injected into the shaping space, such that outsides of the coupling segments of the shoe nails and insides of the slots are filled with the sole material, wherein a cooling process is performed after the feeding of the sole material has stopped to cause the sole material to cool, cure, and turn into a sole and enables the sole to be coupled to the shoe nails in contact with the sole material; and

die opening step: separating the first mold and the second mold, followed by taking out the shoe nails and the sole coupled together.

In order to achieve the above and other objectives, the present invention further provides the sole structure with the shoe nails, comprising: a sole and a plurality of shoe nails coupled thereto, wherein the sole is formed by curing a sole material, wherein the shoe nails each have a head and a coupling segment, with the coupling segment extending in an axial direction, wherein the axial direction is perpendicular to a radial direction, wherein an outer diameter of the coupling segment is less than an outer diameter of the head, such that a filling ring portion is formed between the head and the coupling segment, wherein an end of the coupling segment extends away from the head and has a slot capable of expanding, wherein the slot has a slot bottom, wherein the slot penetrates the coupling segment in the radial direction and communicates with the filling ring portion, wherein the sole material encloses and gets coupled to the filling ring portion and fills the slot via the filling ring portion, such that the sole material covers the slot bottom and fills the filling ring portion.

The present invention is characterized in that: pre-formed shoe nails and thermally molten plastic are disposed in an injection molding mold, and an injection molding process is performed to form a sole and couple the shoe nails and the sole together, so easily as to increase production efficiency and economic benefits.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 (PRIOR ART) is an exploded view of a conventional way of coupling a sole and a shoe nail together;

FIG. 2 is a flowchart of a method of forming a sole and a sole structure with shoe nails coupled thereto according to the present invention;

FIG. 3 is a schematic view of a shoe nail feeding step of the present invention;

FIG. 4 is a schematic view of a die closing step of the present invention;

FIG. 5 is a schematic view of a sole material injecting step of the present invention;

FIG. 6 is a schematic view of a die opening step of the present invention;

FIG. 7 is a perspective view of a manufactured sole structure with shoe nails according to the present invention; and

FIG. 8 is a cross-sectional view of a manufactured sole structure with shoe nails according to the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENT OF THE INVENTION

The present invention provides a method of forming a sole and a sole structure with shoe nails coupled thereto, as shown in FIGS. 2-6. The method comprises the steps below.

Shoe nail pre-forming step (I): forming a shoe nail 20. In this embodiment, the shoe nail 20 is made of rubber. The shoe nail 20 has a head 21 and a coupling segment 22. The coupling segment 22 extends in an axial direction X. A radial direction Y is perpendicular to the axial direction X. The outer diameter of the coupling segment 22 is less than the outer diameter of the head 21, such that a filling ring portion 23 is formed between the head 21 and the coupling segment 22. One end of the coupling segment 22 is connected to the head 21. A slot 221 is disposed at the other end of the coupling segment 22, wherein the slot-disposed end of the coupling segment 22 is different from the head-connected end of the coupling segment 22. The slot 221 has a slot bottom 222 and a slot inner diameter D1. The slot 221 penetrates the coupling segment 22 in the radial direction Y.

Shoe nail feeding step (II): referring to FIG. 3, putting the pre-formed shoe nails 20 in a first mold 30. The first mold 30 has a shaping chamber 31. The shaping chamber 31 has an opening 311. The shaping chamber 31 has therein a plurality of positioning portions 312. Each positioning portion 312 is a concave structure formed by denting the shaping chamber 31. The concave outline of each positioning portion 312 matches the head 21 of a corresponding one of the shoe nails 20. The shoe nails 20 are received at the positioning portions 312 of the shaping chamber 31, respectively. The heads 21 of the shoe nails 20 abut against the positioning portions 312 of the shaping chamber 31, respectively. After the shoe nails 20 have been received in the shaping chamber 31, a shaping space S1 is defined by and between the shoe nails 20 and the opening 311 of the shaping chamber 31.

Die closing step (III): referring to FIG. 3, closing a second mold 40 and the first mold 30. The second mold 40 has a corresponding forming portion 41. The corresponding forming portion 41 protrudes to form a plurality of expanding pins 42. The expanding pins 42 each have an expanding segment 421 and a guiding segment 422 connected to the expanding segment 421. The expanding segment 421 has an expanding segment outer diameter D2. The expanding segment outer diameter D2 is larger than the slot inner diameter D1. The guiding segment 422 is a conic structure which tapers away from the expanding segment 421. A guiding end 423 is disposed at an end of the guiding segment 422 and extends away from the expanding segment 421. The guiding end 423 has a guiding end outer diameter D3. The guiding end outer diameter D3 equals the slot inner diameter D1. A feeding passage 43 is formed to penetrate the corresponding forming portion 41 of the second mold 40. The corresponding forming portion 41 of the second mold 40 faces the shaping chamber 31, so as to close the second mold 40 and the first mold 30, seal the opening 311, and enable communication between the feeding passage 43 and the shaping space S1. As soon as the corresponding forming portion 41 seals the opening 311 exactly, not only are the guiding ends 423 of the expanding pins 42 inserted into the slots 221 of the shoe nails 20, respectively, but the guiding ends 423 of the expanding pins 42 also guide the guiding segments 422 into the slots 221 to abut against the slots 221 and thus allow the slots 221 to expand, respectively, wherein a feeding space S2 is defined by and between the guiding end 423 and the slot bottom 222 of the slot 221.

Sole material injecting step (IV): referring to FIG. 4, heating and melting a sole material M to a liquid state, followed by injecting the molten sole material M into the space between the first mold 30 and the second mold 40 via the feeding passage 43, wherein the sole material M is different from the material of which the shoe nails 20 are made. In this embodiment, the sole material M is molten plastic.

Forming binding step (V): after the sole material M has been injected into the shaping space S1, the thermally molten sole material M fills the shaping space S1, the filling ring portion 23, and the feeding space S2, such that the outsides of the coupling segments 22 of the shoe nails 20 and the insides of the slots 221 are filled with the sole material M. A cooling process is performed after the feeding of the sole material M has stopped. The cooling process causes the sole material M to cool, cure, and turn into a sole A and enables the sole A to be coupled to the shoe nails 20 in contact with the sole material M.

Die opening step (VI): separating the first mold 30 and the second mold 40, followed by taking out the shoe nails 20 and the sole A coupled together.

Referring to FIGS. 7, 8, the aforesaid method is characterized in that: a plurality of shoe nails 20 is coupled to the sole A; the sole A is formed by curing the sole material M; the shoe nails 20 each have the head 21 and the coupling segment 22; the coupling segment 22 extends in the axial direction X, wherein the axial direction X is perpendicular to the radial direction Y; the outer diameter of the coupling segment 22 is less than the outer diameter of the head 21, such that the filling ring portion 23 is formed between the head 21 and the coupling segment 22; one end of the coupling segment 22 extends away from the head 21 and has the slot 221 capable of expanding; the slot 221 has the slot bottom 222; the slot 221 penetrates the coupling segment 22 in the radial direction Y and communicates with the filling ring portion 23; the sole material M of the sole A encloses and gets coupled to the filling ring portion 23 and fills the slot 221 via the filling ring portion 23, such that the sole material M covers the slot bottom 222 and fills the filling ring portion 23 fully.

The process flow of the method of forming a sole and a sole structure with shoe nails coupled thereto and the sole structure with the shoe nails according to the present invention are described above. As indicated above, the present invention is characterized in that: the shoe nails 20 made of a material different from the sole A are pre-formed; the sole A and the shoe nails 20 coupled thereto can be formed concurrently, provided that the shoe nails 20 are positioned between the first mold 30 and the second mold 40 and a conventional injection molding process is performed. The present invention is advantageous in that: the filling ring portions 23 of the shoe nails 20, together with the structure of the expanding pins 42 of the second mold 40, enable the slots 221 of the shoe nails 20 to expand and the feeding space S2 to form in the die closing step (III); hence, the sole material M fills the shaping space S1, the filling ring portion 23, and the feeding space S2 in sole material injecting step (IV). In addition, the filling ring portion 23 and the feeding space S2 are directly constructed outside the coupling segment 22 of each shoe nail 20 and inside each slot 221, and thus the sole material M forms the sole A while being precisely coupled to the shoe nails 20. Accordingly, process flow of the overall forming process is so simple that it increases production efficiency and economic benefits markedly.

Since the sole material M is heated and melted to a liquid state in sole material injecting step (IV), the sole material a adheres to the surfaces of in the shoe nails 20 fully and evenly at the end of sole material injecting step (IV). Hence, the sole material M is cooled and formed while getting coupled to the shoe nails 20 firmly. Accordingly, the sole A and the shoe nails 20 are firmly coupled together, even though the sole A is different from the shoe nails 20 in terms of the materials they are made of, respectively. 

What is claimed is:
 1. A method of forming a sole and a sole structure with shoe nails coupled thereto, the method comprising: shoe nail pre-forming step: forming shoe nails, wherein the shoe nails each have a head and a coupling segment, with the coupling segment extending in an axial direction, wherein the axial direction is perpendicular to a radial direction, wherein an outer diameter of the coupling segment is less than an outer diameter of the head such that a filling ring portion is formed between the head and the coupling segment, wherein, an end of the coupling segment is connected to the head, wherein a slot is disposed at another end of the coupling segment and has a slot bottom and a slot inner diameter, wherein the slot penetrates the coupling segment in the radial direction; shoe nail feeding step: putting the pre-formed shoe nails in a first mold, wherein the first mold has a shaping chamber, and the shaping chamber has an opening, wherein, after the shoe nails have been received in the shaping chamber, a shaping space is defined by and between the shoe nails and the opening of the shaping chamber; die closing step: closing a second mold and the first mold, wherein the second mold has a corresponding forming portion protruding to form a plurality of expanding pins, wherein the expanding pins each have an expanding segment and a guiding segment connected to the expanding segment, wherein the expanding segment has an expanding segment outer diameter, wherein the expanding segment outer diameter is larger than the slot inner diameter, wherein the guiding segment is a conic structure which tapers away from the expanding segment, wherein a guiding end is disposed at an end of the guiding segment and extends away from the expanding segment, wherein the guiding end has a guiding end outer diameter, with the guiding end outer diameter being equal to the slot inner diameter, wherein a feeding passage penetrates the corresponding forming portion of the second mold, wherein the corresponding forming portion of the second mold faces the shaping chamber, so as to close the second mold and the first mold, seal the opening, and enable communication between the feeding passage and the shaping space, wherein, as soon as the corresponding forming portion seals the opening exactly, not only are the guiding ends of the expanding pins inserted into the slots of the shoe nails, respectively, but the guiding ends of the expanding pins also guide the guiding segments into the slots to abut against the slots and thus allow the slots to expand, respectively, wherein a feeding space is defined by and between the guiding end and the slot bottom; sole material injecting step: heating and melting a sole material to a liquid state, followed by injecting the molten sole material into a space between the first mold and the second mold via the feeding passage; forming binding step: filling the shaping space, the filling ring portion, and the feeding space with the thermally molten sole material after the sole material has been injected into the shaping space, such that outsides of the coupling segments of the shoe nails and insides of the slots are filled with the sole material, wherein a cooling process is performed after the feeding of the sole material has stopped to cause the sole material to cool, cure, and turn into a sole and enables the sole to be coupled to the shoe nails in contact with the sole material; and die opening step: separating the first mold and the second mold, followed by taking out the shoe nails and the sole coupled together.
 2. The method of claim 1, wherein the shoe nails are made of a material different from the sole material.
 3. The method of claim 2, wherein the shoe nails are made of rubber, and the sole material is molten plastic.
 4. The method of claim 1, wherein the shaping chamber of the first mold has therein a plurality of positioning portions, with each said positioning portion being a concave structure formed by denting the shaping chamber, wherein a concave outline of each said positioning portion matches the head of a corresponding one of the shoe nails, wherein, in the shoe nail feeding step, the shoe nails are received at the positioning portions, respectively, and the heads abut against the positioning portions of the shaping chamber, respectively.
 5. A sole structure with shoe nails, comprising a sole and a plurality of shoe nails coupled thereto, wherein the sole is formed by curing a sole material, wherein the shoe nails each have a head and a coupling segment, with the coupling segment extending in an axial direction, wherein the axial direction is perpendicular to a radial direction, wherein an outer diameter of the coupling segment is less than an outer diameter of the head, such that a filling ring portion is formed between the head and the coupling segment, wherein an end of the coupling segment extends away from the head and has a slot capable of expanding, wherein the slot has a slot bottom, wherein the slot penetrates the coupling segment in the radial direction and communicates with the filling ring portion, wherein the sole material encloses and gets coupled to the filling ring portion and fills the slot via the filling ring portion, such that the sole material covers the slot bottom and fills the filling ring portion. 